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flower flies


What do they look like?

Adult flies of many species in this family are mimics of bees or wasps. They are mostly black with yellow or orange stripes. A few others are brown, or metallic green or blue (these may also be mimics of bees). They have large eyes and short mouthparts formed into a tube with a sponge at the end. Their bodies may be slim or stout and are sometimes flattened top-to-bottom. Some species wag they abdomens up and down when they land. Like all flies they only have two wings, their hind wings are reduced (see More Information about True Flies for more).

Larvae are more variable. They are all legless and headless, but some aquatic species have long breathing tubes on their hind ends, some have tough skins, some look like little slugs. Color varies from white to brown to green.

  • Sexual Dimorphism
  • sexes alike
  • female larger
  • Range length
    4.0 to 25.0 mm
    0.16 to 0.98 in

Where do they live?

This family of flies is found all over the world, and there are thousands of species. Nobody knows exactly how many species there are in Michigan or in the whole Great Lakes region, but it is probably more than 150.

What kind of habitat do they need?

Adult Flower Flies are found (surprise!) around flowers. They are also found near places where their larvae might live and feed and this is variable (see below).

Flower Fly larvae live in many different types of habitats. Some live in still or slow-moving freshwater, some live in decaying wood, some live in dung, some on plants, and some in the nests of other insects.

  • Aquatic Biomes
  • lakes and ponds
  • rivers and streams

How do they grow?

Flower Flies have complete metamorphosis, see More Information under True Flies for the basic fly life cycle. In cold climates they spend the winter as larvae or pupae.

How long do they live?

Most Flower Flies live a year or less, but some aquatic species that live in cold climates may survive as larvae for several years before metamorphosing into adults.

How do they behave?

Adult Flower Flies are only active on warm sunny days. Larvae may be active any time. Some species travel long distances, but most stay close to where they grew up. They are always solitary, only coming together for mating. One group of aquatic larvae have evolved a special way of getting air without going to the surface of the water, they have sharp structures on their abdomen that they stab into hollow reeds growing in the water. The reeds have air inside them, and the fly larvae breath that.

How do they communicate with each other?

These flies find each other by sight, sound, and maybe scent. They have good wide-angle vision to find each other and watch out for predators. They can continue to make vibration noise by moving structures in their thorax even when they are not moving or flapping their wings.

What do they eat?

Adult flower flies feed on nectar from flowers and from aphid "honeydew" (see Aphids).

The larvae of different species feed on different kinds of food. Some feed on decaying, damp plant material, on fungi or on green plants, some on the bulbs of plants in the lily family, some in dung. Many are aquatic and live in shallow freshwater (sometimes in water that seems foul and polluted), some in water-filled treeholes. Some species are scavengers in the nests of ants or wasps. Some of the most amazing are predators on slow-moving, soft-skinned insects like aphids. These predators have no eyes and no legs, but they still hunt and eat these little insects.

What eats them and how do they avoid being eaten?

Adult flower flies rely on their high-speed flight and their similarity to stinging insects to avoid or discourage many predators. Larvae hide in muck and mud, and some live only in small treeholes where there are not very many predators. The species that live in nests of ants and wasps have adjusted their scent so they don't smell like food, and they stay out of the way of the other insects as much as they can.

What roles do they have in the ecosystem?

Flower Flies are imporant pollinators of many flowers. Their larvae help clean up and break down dead plants, and feed on micro-organisms.

  • Ecosystem Impact
  • pollinates

Do they cause problems?

A few species of Flower Flies have larvae that damage bulbs or green plants that are valuable to humans. They are not a major agricultural pest, but they do sometimes cause damage.

  • Ways that these animals might be a problem for humans
  • crop pest

How do they interact with us?

These flies can be important pollinators, and some species feed on aphids that are pests.

  • Ways that people benefit from these animals:
  • pollinates crops
  • controls pest population

Are they endangered?

No Flower Fly species are currently known to be endangered in the United States, but some species in other countries are considered endangered and at risk of extinction.

  • IUCN Red List [Link]
    Not Evaluated



Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

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living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

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living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

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living in the southern part of the New World. In other words, Central and South America.

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living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

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bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends.


a wetland area rich in accumulated plant material and with acidic soils surrounding a body of open water. Bogs have a flora dominated by sedges, heaths, and sphagnum.


an animal that mainly eats meat


mid-altitude coastal areas with mild, rainy winters and long, dry summers. Dominant plant types are dense, evergreen shrubs.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

  1. active during the day, 2. lasting for one day.

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature


union of egg and spermatozoan


forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.


mainly lives in water that is not salty.


An animal that eats mainly plants or parts of plants.

internal fertilization

fertilization takes place within the female's body


referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


marshes are wetland areas often dominated by grasses and reeds.


A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.


having the capacity to move from one place to another.


This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oceanic islands

islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.


found in the oriental region of the world. In other words, India and southeast Asia.

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reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.


the regions of the earth that surround the north and south poles, from the north pole to 60 degrees north and from the south pole to 60 degrees south.


rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Climbing plants are also abundant. There is plenty of moisture and rain, but may be somewhat seasonal.

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season


remains in the same area


reproduction that includes combining the genetic contribution of two individuals, a male and a female


lives alone


a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.


this biome is characterized by large expanses of coniferous forest, there is an extended cold season and heavy snowfall.


that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).


Living on the ground.


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


A terrestrial biome found in very cold places -- either close to polar regions or high on mountains. Part of the soil stays frozen all year. Few kinds of plants grow here, and these are low mats or shrubs not trees. The growing season is short.

University of Michigan Museum of ZoologyNational Science Foundation

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. "Syrphidae" (On-line), Animal Diversity Web. Accessed April 20, 2014 at

BioKIDS is sponsored in part by the Interagency Education Research Initiative. It is a partnership of the University of Michigan School of Education, University of Michigan Museum of Zoology, and the Detroit Public Schools. This material is based upon work supported by the National Science Foundation under Grant DRL-0628151.
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